ICD-9 versus ICD-10

According to the
American Medical Association (AMA) ICD-9-CM contains approximately 13,000
codes. ICD-10, both the clinical modification (ICD-10-CM) for diagnosis coding,
and the procedural coding system (ICD-10-PCS) will contain 68,000 available codes.
Many of these additional codes fall within ICD-10-PCS, which will replace Volume 3 of ICD-9-CM,
but the diagnosis coding methodology will also be affected.

ICD-9-CM codes
are between three and five characters in length. ICD-10-CM code are between
three and seven characters. Most ICD-9 codes are composed of numbers only,
except codes that start with E, which are used to describe causes of injury,
and codes that start with V, which are used to describe conditions that are not
diseases or symptoms that lead to medical encounters. In ICD-10, all codes will
start with a letter, to identify where in the coding system a described
condition or procedure falls within the overall coding methodology.

The ICD-9 coding
system has little room for new codes. ICD-10 offers more room to add new codes
within the established framework. ICD-9 contains many vague codes, while ICD-10
allows for more specific codes. Granularity of reported data is an important
concern when tracking the utilization and effectiveness of medical services. It
is expected that the implementation of ICD-10 will allow for more transparency,
and for more accurate reporting of procedures, diseases, and symptoms, than has
been possible before. Finally, ICD-9 does not capture the laterality of a
condition or procedure. ICD-10 contains digits appended to codes to convey
whether a condition happened on the right side or the left side. This creates
transparency, so that third-party payers and statisticians can recognize a new
injury from a pre-existing condition.